Coordinate measuring machine with rotatable grip

ABSTRACT

A portable coordinate measuring machine (PCMM) can have one or more rotatable grip assemblies to provide a locations for an operator to grasp the PCMM. A rotatable grip assembly can include a rotatable sleeve, a grip portion disposed over the sleeve, and one or more retaining rings to prevent the rotatable grip from axially sliding along one or more members of an articulated arm PCMM. A PCMM can include two rotatable grips to allow an operator to grasp the PCMM with both hands for positioning and repositioning operations. One rotatable grip can be positioned on an arm member most distant the PCMM base, and another rotatable grip can be positioned on a housing at least partially encasing an articulating joint assembly coupled to the arm member most distant the PCMM base. Other numbers of and locations of rotatable grip assemblies can be used in PCMMs.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present application relates to measurement devices, and moreparticularly, to articulated arm coordinate measuring.

2. Description of the Related Art

Rectilinear measuring systems, also referred to as coordinate measuringmachines (PCMM's) and articulated arm measuring machines, are used togenerate geometry information. In general, these instruments capture thestructural characteristics of an object for use in quality control,electronic rendering and/or duplication. One example of a conventionalapparatus used for coordinate data acquisition is a portable coordinatemeasuring machine (PCMM), which is a portable device capable of takinghighly accurate measurements within a measuring sphere of the device.Such devices often include a probe mounted on an end of an arm thatincludes a plurality of transfer members connected together by joints.The end of the arm opposite the probe is typically coupled to a moveablebase. Typically, the joints are broken down into singular rotationaldegrees of freedom, each of which is measured using a dedicatedrotational transducer. During a measurement, the probe of the arm ismoved manually by an operator to various points in the measurementsphere. At each point, the position of each of the joints must bedetermined at a given instant in time. Accordingly, each transduceroutputs an electrical signal that varies according to the movement ofthe joint in that degree of freedom. Typically, the probe also generatesa signal. These position signals and the probe signal are transferredthrough the arm to a recorder/analyzer. The position signals are thenused to determine the position of the probe within the measurementsphere. See e.g., U.S. Pat. Nos. 5,829,148 and 7,174,651.

Typically, when PCMMs are used, an operator positions his hands atvarious locations along the arms and joints of the PCMM to move theprobe into a desired position for data acquisition. During the course ofa measurement session, an operator may move his hands significantly toposition and reposition the PCMM. Additionally, different operators mayposition their hands at different locations along the PCMM. Accordingly,it can be difficult to initially calibrate a PCMM to account for thevarious loads applied by different operators at different locationsalong the PCMM.

As mentioned above, the purpose of PCMM's is to take highly accuratemeasurements. Accordingly, there is a continuing need to improve theaccuracy of such devices.

SUMMARY OF THE INVENTION

In some embodiments, a coordinate measuring machine is provided thatcomprises a first transfer member, a second transfer member, anarticulating joint assembly, and a rotatable grip assembly. Thearticulating joint assembly rotatably couples the first transfer memberto the second transfer member. The rotatable grip assembly is disposedon an outer surface of one of the first transfer member and the secondtransfer member.

In other embodiments, a coordinate measuring machine is provided thatcomprises a base, a first transfer member, a second transfer member, afirst articulation joint assembly, a third transfer member, a secondarticulation joint assembly, and a rotatable grip assembly. The firsttransfer member is coupled to the base. The second transfer member isrotatably coupled to the first transfer member by the first articulationjoint assembly. The third transfer member is rotatably coupled to thesecond transfer member by the second articulation joint assembly. Therotatable grip assembly is disposed on the third transfer member.

In other embodiments, a coordinate measuring machine is provided thatcomprises a base, a first transfer member, a first articulation member,a second transfer member, a second articulation member, a thirdarticulation member, a first housing, a second housing, a firstrotatable grip assembly, and a second rotatable grip assembly. The firsttransfer member is coupled to the base. The second transfer member isrotatably coupled to the first transfer member by the first articulationmember. The third transfer member is rotatably coupled to the secondtransfer member by the second articulation member. The first housing isdisposed about at least a portion of the first articulation member. Thesecond housing is disposed about at least a portion of the secondarticulation member. The first rotatable grip assembly is disposed onthe third transfer member and rotatable about a longitudinal axisdefined by the third transfer member. The second rotatable grip assemblyis disposed on the second housing and rotatable about the longitudinalaxis.

In some embodiments, a coordinate measuring machine comprises a firsttransfer member, a second transfer member, an articulating jointassembly, and a probe caddie. The articulating joint assembly rotatablycouples the first transfer member to the second transfer member. Theprobe caddie is disposed on the coordinate measuring machine and isadapted to receive at least one probe.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the presentinventions will now be described in connection with various embodiments,in reference to the accompanying drawings. The illustrated embodiments,however are merely examples and are not intended to limit theinventions. The drawings include the following figures:

FIG. 1 illustrates a perspective view of one embodiment of a coordinatemeasuring machine

FIG. 2A illustrates a perspective view of the coordinate measuringmachine of FIG. 1 in a first position with an operator's handspositioned on rotatable grips thereof.

FIG. 2B illustrates a perspective view of the coordinate measuringmachine of FIG. 1 in a second position with the operator's handspositioned on rotatable grips thereof.

FIG. 3 illustrates a cutaway view of a transfer member of the coordinatemeasuring machine of FIG. 1.

FIG. 4 illustrates an exploded perspective view of the transfer memberof FIG. 3.

FIG. 5A illustrates a probe caddie for use with a coordinate measuringmachine such as that illustrated in FIG. 1.

FIG. 5B illustrates the probe caddie of FIG. 5A with various probesremoved.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 illustrates one embodiment of a coordinate measuring machine(PCMM) 10. In the illustrated embodiment, the PCMM 10 comprises a base20, a plurality of substantially rigid, transfer members 24, 26, and 28,a coordinate acquisition member 30, and a plurality of articulationmembers 40, 42, 44, 46, 48, 50 connecting the rigid transfer members 24,26, 28 to one another. Each articulation member is configured to impartone or more rotational and/or angular degrees of freedom. Thearticulation members 40, 42, 44, 46, 48, and 50 allow the transfermembers 24, 26, 28 of the PCMM 10 to be aligned in various spatialorientations thereby 38 allowing fine positioning of a coordinateacquisition member 30 in three-dimensional space.

The position of the rigid transfer members 24, 26, 28 and the coordinateacquisition member 30 may be adjusted manually, or using, robotic,semi-robotic, and/or any other adjustment method. In one embodiment, thePCMM 10, through the various articulation members 40, 42, 44, 46, 48,50, is provided with six rotary axes of movement. However, there is nostrict limitation to the number or order of axes of movement that may beused, and, in other embodiments, a PCMM can have more or fewer axes ofmovement.

In the embodiment of PCMM 10 illustrated in FIG. 1, the articulationmembers 40, 42, 44, 46, 48, 50 can be divided into two functionalgroupings based on their operation, namely: 1) those articulationmembers 40, 44, and 48 which allow the swiveling motion associated witha specific transfer member (hereinafter, “swiveling joints”), and 2)those articulation members 42, 46, and 50 which allow a change in therelative angle formed between two adjacent members or between thecoordinate acquisition member 30 and its adjacent member (hereinafter,“hinge joints”). While the illustrated embodiment includes threeswiveling joints and three hinge joints positioned as to create six axesof movement, it is contemplated that in other embodiments, the number ofand location of hinge joints and swiveling joints can be varied toachieve different movement characteristics in a PCMM. For example, asubstantially similar device with seven axes of movement could simplyhave an additional swivel joint between the coordinate acquisitionmember 30 and articulation member 50. In still other embodiments, theswiveling joints and hinge joints can be combined and/or used indifferent combinations.

The coordinate acquisition member 30 can comprise a contact sensitivemember or hard probe 32 configured to engage surfaces of a selectedobject and/or generate coordinate data on the basis of probe contact asis known in the art. Alternatively, the coordinate acquisition member 30can comprise a remote scanning and detection component that does notnecessarily require direct contact with the selected object to acquiregeometry data. In one embodiment, a laser coordinate detection device(e.g., laser camera) can be used to obtain geometry data without directobject contact. It will be appreciated that in various embodiments ofPCMM, various coordinate acquisition member 30 configurations can beused including: a contact-sensitive probe, a remote-scanning probe, alaser-scanning probe, a probe that uses a strain gauge for contactdetection, a probe that uses a pressure sensor for contact detection, aprobe that used an infrared beam for positioning, and a probe configuredto be electrostatically-responsive can be used for the purposes ofcoordinate acquisition.

With continued reference to FIG. 1, in various embodiments of the PCMM10, the various devices which may be used for coordinate acquisition,such as the probe 32, may be configured to be manually disconnected andreconnected from the PCMM 10 such that an operator can change coordinateacquisition devices without specialized tools. Thus, an operator canquickly and easily remove one coordinate acquisition device and replaceit with another coordinate acquisition device. Such a connection maycomprise any quick disconnect or manual disconnect device. This rapidconnection capability of a coordinate acquisition device can beparticularly advantageous in a PCMM 10 that can be used for a widevariety of measuring techniques (e.g. measurements requiring physicalcontact of the coordinate acquisition member with a surface followed bymeasurements requiring only optical contact of the coordinateacquisition member) in a relatively short period of time.

In the embodiment of FIG. 1, the coordinate acquisition member 30 alsocomprises buttons 66, which are configured to be accessible by anoperator. By pressing one or more of the buttons 66 singly, multiply, orin a preset sequence, the operator can input various commands to thePCMM 10. In some embodiments the buttons 66 can be used to indicate thata coordinate reading is ready to be recorded. In other embodiments thebuttons 66 can be used to indicate that the location being measured is ahome position and that other positions should be measured relative tothe home position. In other embodiments the buttons may be used to turnon or off the PCMM 10. In other embodiments, the buttons 66 can beprogrammable to meet an operator's specific needs. The location of thebuttons 66 on the coordinate acquisition member 30 can be advantageousin that an operator need not access the base 20 or a computer in orderto activate various functions of the PCMM 10 while using the coordinateacquisition member 30. This positioning may be particularly advantageousin embodiments of PCMM having transfer members 24, 26, or 28 that areparticularly long, thus placing the base 20 out of reach for an operatorof the coordinate acquisition member 30. In some embodiments of the PCMM10, any number of operator input buttons (e.g., more or fewer than thethree illustrated in FIG. 1), can be provided, which may be placed invarious other positions on the coordinate acquisition member 30 oranywhere on the PCMM 10. Other embodiments of PCMM can include otheroperator input devices positioned on the PCMM or the coordinateacquisition member 30, such as switches, rotary dials, or touch pads inplace of, or in addition to operator input buttons.

With continued reference to FIG. 1, in some embodiments, the base 20further comprises magnetic attachment mounts 60 that can attach the base20 to a metallic work surface. The magnetic attachment mounts 60 candesirably be selectively engaged so that an operator can position thePCMM 10 on to a work surface then engage the magnetic attachment mounts60 once the PCMM 10 has been placed in a desirable position. In otherembodiment, the base 20 can be coupled to a work surface through avacuum mount, bolts or other coupling devices. Additionally, in someembodiments, the base 20 can comprise various electrical interfaces suchas plugs, sockets, or attachment ports 62. In some embodiments,attachment ports 62 can comprise connectability between the PCMM 10 anda USB interface for connection to a processor such as a general purposecomputer, an AC power interface for connection with a power supply, or avideo interface for connection to a monitor. In some embodiments, thePCMM 10 can be configured to have a wireless connection with an externalprocessor or general purpose computer such as by a WiFi connection,Bluetooth connection, RF connection, infrared connection, or otherwireless communications protocol. In some embodiments, the variouselectrical interfaces or attachment ports 62 can be specificallyconfigured to meet the requirements of a specific PCMM 10.

With continued reference to FIG. 1, in some embodiments, the base 20 ofthe PCMM 10 can also include a self contained power source 64 such as abattery. Embodiments of PCMM 10 having a self contained power source canbe easily moved to various locations that do not have easy access to apower source such as an AC power outlet, allowing enhanced flexibilityin the operating environment of the PCMM 10. In one embodiment, theself-contained power source 64 can be a lithium-ion rechargeable batterythat can provide power to the PCMM for periods of use away from a poweroutlet. In other embodiments, the self-contained power source 64 can beother types of rechargeable batteries such as nickel cadmium, nickelmetal hydride, or lead acid batteries. In other embodiments, theself-contained power source 64 can be a single use battery such as analkaline battery.

With continued reference to FIG. 1, the transfer members 24, 26, and 28are preferably constructed of hollow generally cylindrical tubularmembers so as to provide substantial rigidity to the members 24, 26, and28. The transfer members 24, 26, and 28 can be made of any suitablematerial which will provide a substantially rigid extension for the PCMM10. As will be discussed in greater detail below, the transfer members24, 26, and 28 preferably define a double tube assembly so as to provideadditional rigidity to the transfer members 24, 26, and 28. Furthermore,it is contemplated that the transfer members 24, 26, and 28 in variousother embodiments can be made of alternate shapes such as thosecomprising a triangular or octagonal cross-section.

In some embodiments, it can be desirable to use a composite material,such as a carbon fiber material, to construct at least a portion of thetransfer members 24, 26, and 28. In some embodiments, other componentsof the PCMM 10 can also comprise composite materials such as carbonfiber materials. Constructing the transfer members 24, 26, 28 ofcomposite such as carbon fiber can be particularly advantageous in thatthe carbon fiber can react less to thermal influences as compared tometallic materials such as steel or aluminum. Thus, coordinate measuringcan be accurately and consistently performed at various temperatures. Inother embodiments, the transfer members 24, 26, 28 can comprise metallicmaterials, or can comprise combinations of materials such as metallicmaterials, ceramics, thermoplastics, or composite materials. Also, aswill be appreciated by one skilled in the art, many of the othercomponents of the PCMM 10 can also be made of composites such as carbonfiber. Presently, as the manufacturing capabilities for composites aregenerally not as precise when compared to manufacturing capabilities formetals, generally the components of the PCMM 10 that require a greaterdegree of dimensional precision are generally made of a metals such asaluminum. It is foreseeable that as the manufacturing capabilities ofcomposites improved that a greater number of components of the PCMM 10can be also made of composites.

With continued reference to FIG. 1, some embodiments of the PCMM 10 mayalso comprise a counterbalance system 80 that can assist an operator bymitigating the effects of the weight of the transfer members 26 and 28and the articulating members 44, 46, 48, and 50. In some orientations,when the transfer members 26 and 28 are extended away from the base 20,the weight of the transfer members 26 and 28 can create difficulties foran operator. Thus, a counterbalance system 80 can be particularlyadvantageous to reduce the amount of effort that an operator needs toposition the PCMM for convenient measuring. In some embodiments, thecounterbalance system 80 can comprise resistance units (not shown) whichare configured to ease the motion of the transfer members 26 and 28without the need for heavy weights to cantilever the transfer members 26and 28. It will be appreciated by one skilled in the art that in otherembodiments simple cantilevered counterweights can be used in place orin combination with resistance units.

In the embodiment illustrated in FIG. 1, the resistance units areattached to the transfer member 26 to provide assisting resistance formotion of the transfer members 26 and 28. In some embodiments, theresistance units can comprise hydraulic resistance units which use fluidresistance to provide assistance for motion of the transfer members 26and 28. In other embodiments the resistance units may comprise otherresistance devices such as pneumatic resistance devices, or linear orrotary spring systems.

With continued reference to FIG. 1, the position of the probe 32 inspace at a given instant can be calculated if the length of eachtransfer member 24, 26, and 28 and the specific position of each of thearticulation members 40, 42, 44, 46, 48, and 50 are known. The positionof each of the articulation members 40, 42, 44, 46, 48, and 50 can bemeasured as a singular rotational degree of motion using a dedicatedrotational transducer, which will be described in more detail below.Each transducer can output a signal (e.g., an electrical signal), whichcan vary according to the movement of the 40, 42, 44, 46, 48, 50 in itsdegree of motion. The signal can be carried through wires or otherwisetransmitted to the base 20 of the PCMM 10. From there, the signal can beprocessed and/or transferred to a computer for determining the positionof the probe 32 in space.

In some embodiments of PCMM 10, a rotational transducer for each of thearticulation members 40, 42, 44, 46, 48 . . . , and 50 can comprise anoptical encoder. Various embodiments of optical encoder are discussed inmore detail below with reference to FIGS. 3-6. In general, an opticalencoder measures the rotational position of an axle by coupling ismovement to a pair of internal hubs having successive transparent andopaque bands. In such embodiments, light can be shined through orreflected from the hubs onto optical sensors which feed a pair ofelectrical outputs. As the axle sweeps through an arc, the output of ananalog optical encoder can be substantially two sinusoidal signals whichare 90 degrees out of phase. Coarse positioning can be determinedthrough monitoring a change in polarity of the two signals. Finepositioning can be determined by measuring an actual value of the twosignals at a specific time. In certain embodiments, enhanced accuracycan be obtained by measuring the output precisely before it is corruptedby electronic noise. Thus, digitizing the position information before itis sent to the processor or computer can lead to enhanced measurementaccuracy.

As will be described in detail below, in the illustrated embodiment, thearticulation members 40, 42, 44, 46, 48 . . . , and 50 can be dividedinto two general categories, namely: 1) articulation members 40, 44, 48,which allow swiveling motion of a transfer member 24, 26, 28 and arethus sometimes referred to as “swivel members” 40, 44, 48 herein and 2)articulation members 42, 46 and 50, which allow for change in therelative angle formed between two adjacent members and are sometimesreferred to herein as “pivot or hinge members” 42, 46, 50.

While several embodiment and related features of a PCMM 10 have beengenerally discussed herein, additional details and embodiments of PCMM10 can be found in U.S. Pat. Nos. 5,829,148 and 7,174,651, the entiretyof these patents are hereby incorporated by reference herein. Whilecertain features below are discussed with reference to the embodimentsof PCMM 10 described above, it is contemplated that they can be appliedin other embodiments of PCMM such as those described in U.S. Pat. No.5,829,148 or 7,174,651, U.S. patent application Ser. No. 11/963,531,filed Dec. 21, 2007, entitled “IMPROVED JOINT AXIS FOR COORDINATEMEASUREMENT MACHINE”, U.S. patent application Ser. No. 11/943,463, filedNov. 20, 2007, entitled “COORDINATE MEASUREMENT DEVICE WITH IMPROVEDJOINT” and U.S. patent application Ser. No. 11/775,081, filed Jul. 9,2007, entitled “JOINT FOR COORDINATE MEASUREMENT DEVICE”, the entirecontents of these patents and patent applications being incorporatedherein by reference.

With reference to FIGS. 1, 2A, and 2B, in some embodiments, the PCMM 10can comprise one or more rotatable grip assemblies 100. In theillustrated embodiment, the PCMM 10 can comprise a lower rotatable gripassembly 102 and an upper rotatable grip assembly 104. Advantageously,having a lower rotatable grip assembly 102 and an upper rotatable gripassembly 104 disposed on the transfer member 28, allows the operator toeasily use both hands in positioning the PCMM 10. In other embodiments,the PCMM 10 can comprise one, or more than two rotatable grips.

Certain desirable characteristics of a manually operated articulated armPCMM are that the PCMM is easy to articulate by an operator and accuratein its measurement. One advantage of a rotatable grip assembly 100 asdescribed herein is that it can make the PCMM easier for an operator toarticulate. The rotatable grip assembly 100 rolls through the operator'shands with the grip relieving the majority of the friction that wouldnormally exist between the operator's hand and the transfer member ofthe PCMM.

Another advantage of the easy, ergonomic, and low friction operation ofthe rotatable grip assembly 100 is a more accurate PCMM. When anoperator positions a hand on the transfer member of the PCMM,variability of fictional forces between the operator and the PCMM can bea source of error in the accuracy of a PCMM's measurement. When anoperator's hand is not on a rotatable grip assembly 100, fictionalforces between the operator's hand and the transfer member of the PCMMcan change as the operator articulates the arm into different positions.Further these forces can vary as the operator stiffens or loosens hisgrip on the arm. These forces also vary from one operator to another.

Some previous PCMMs have had over designed joint assemblies tocompensate for the variability in fictional forces and the variabilityand in positions in which an operator may grasp the PCMM. These jointassemblies resulted in a PCMM that was relatively heavy and costly.Other PCMMs have included costly strain sensors or additional encoderread heads in order to compensate for operator forces. Advantageously, aPCMM with one or more rotatable grip assemblies 100 can reduce operatorforces on the PCMM in a cost-efficient manner.

Desirably, the rotatable grip assemblies 100 can rotate freely andinfinitely about a portion of the PCMM 10. This free and infiniterotation allows an operator to easily grasp the rotatable grips 100 andposition the PCMM 10 as desired. In other embodiments the rotatablegrips 100 can rotate through a predetermined range defined by rotationalstops.

With reference to FIGS. 2A and 2B, an operator may grasp the PCMM 10using the grip assemblies 102, 104. As the operator moves the PCMM 10from a first position (illustrated in FIG. 2A) to a second position(illustrated in FIG. 2B), the grip assemblies 102, 104 can rotate toaccommodate this motion. Thus, advantageously, an operator need notreposition one or both of his hands as he repositions the PCMM 10.

Another advantage of the rotatable grips 100 is increased accuracy ofthe measurements obtained. Previously, operators would position theirhands at any convenient location along the transfer member 28.Accordingly, the PCMM 10 could experience slightly differentoperator-induced load conditions depending on the position of theoperator's hands. While the PCMM 10 can be calibrated to account for theposition of an operator's hands at an expected location, previously,there would be no indication that an operator would place his hands atthis expected location. However, the rotatable grips 100 provideprescribed locations upon which an operator is to position his hands.Thus, advantageously, the PCMM 10 can be calibrated with a knownposition of the operator's hands on the PCMM 10. Accordingly, variationsin PCMM accuracy due to variations in positioning of individualoperators' hands can be minimized.

Furthermore, the rotatable grips 100 can be positioned on the PCMM 10 ata location where relatively little force is required to position thePCMM 10. Accordingly, a PCMM 10 having rotatable grips 100 so positionedwould have enhanced durability and reliability as it would likelyencounter lower loading during routine use than a PCMM without rotatablegrips 100.

With continued reference to FIGS. 1, 2A, and 2B, in the illustratedembodiment, the rotatable grip assemblies 100 can be disposed on thetransfer member 28 furthest away from the base 20. Desirably, operatorstypically position the PCMM 10 using this transfer member 28. Operatorstypically position one hand adjacent the probe and another either alongthe transfer member 28 or at an end of the transfer member 28 oppositethe probe, as illustrated in phantom lines in FIGS. 2A and 2B. In theillustrated embodiment, the PCMM 10 includes two rotatable gripsassemblies 100, one at each typical operator grasping location. In otherembodiments, rotatable grip assemblies 100 can be disposed on othertransfer members 26, 24 in addition to or instead of the rotatable grips102, 104 on transfer member 28 furthest away from the base 20.

With reference to FIGS. 3 and 4, construction of the illustratedembodiment of upper and lower rotatable grip assemblies 102, 104 isfurther described.

FIG. 3 illustrates the longitudinal cross-sectional view of transfermember 28 with rotatable grips 102, 104 likewise illustrated incross-section. FIG. 4 illustrates an exploded assembly view of transfermember 28 including rotatable grips 102, 104.

With continued reference to FIGS. 3 and 4, lower rotatable grip 102 cancomprise a rotatable sleeve 110 disposed over an outer surface oftransfer member 28, a grip portion 112, an upper retaining ring 114, anda lower retaining ring 116. The rotatable sleeve 110 can be constructedof a material having a relatively low coefficient of friction. Forexample, the rotatable sleeve 110 can be constructed of a syntheticmaterial such as can be found in a bushing, for example, a nylon orDelrin® material. Desirably, the rotatable sleeve 110 can rotate freelywith respect to an outer surface of the transfer member 28 and surfacesof the upper retaining ring 114 and the lower retaining ring 116. Therotatable sleeve 110 can have a generally cylindrical body with flangedlips at a first end and a second end thereof. The flanged lips on therotatable sleeve 110 can retain the grip portion 112.

With continued reference to FIGS. 3 and 4, the grip portion 112 can havea generally cylindrical shape and be sized to snugly fit over therotatable sleeve 110. The grip portion 112 can comprise a relativelysoft material such as a natural or synthetic rubber, or a siliconerubber for operator gripability and comfort. In the illustratedembodiment, the rotatable sleeve 110 and grip portion 112 are separatelyformed such that the rotatable sleeve 110 can allow for free rotation ofthe rotatable grip 102 and the grip portion 112 can provide enhancedoperator gripability and comfort. In some embodiments, the grip portion112 can be relatively elastic and can be stretch fit over the rotatablesleeve 110. In some embodiments, the grip portion 112 can be adhered tothe rotatable sleeve 110 using an adhesive or epoxy. In otherembodiments, the rotatable sleeve 110 in the grip portion 112 can beintegrally formed of a material having satisfactory material propertieswith respect to friction and operator comfort.

With continued reference to FIGS. 3 and 4, to further enhance thegripability of the grip portion 112, in some embodiments, the gripportion 112 can include gripping features such as, for example, one ormore dimples or indentations 113, one or more protrusions or ridges, orsurface texturing. Advantageously, this enhanced gripability can reducethe likelihood an operator's hand will slip from the rotatable grip 102while the operator is positioning the PCMM 10.

With continued reference to FIGS. 3 and 4, the upper and lower retainingrings 114, 116 can maintain an axial position of the lower rotatablegrip 102 with respect to the transfer member 28. In some embodiments,the retaining rings 114, 116 can be constructed of a metallic materialand can be sized to be press fit onto the transfer member 28 and tolimit axial movement of the rings 114, 116 on the transfer member 28once positioned. In other embodiments, the retaining rings can comprisenonmetallic materials such as plastics, composite materials, or othermaterials. Desirably, the retaining rings 114, 116 can be constructed ofa material having material properties and a surface finish that allowthe rotatable sleeve 110 to freely rotate between the retaining rings114, 116. In some embodiments, the outer surface of the transfer member28 can include at least one recess configured to receive at least one ofthe retaining rings 114, 116. In other embodiments, the rotatable gripassembly 100 does not include retaining rings 114, 116. Thus, therotatable grip assembly could move axially thereby enhancing positioningease for the operator.

With continued reference to FIGS. 3 and 4, the upper rotatable grip 104is illustrated. The upper rotatable grip 104 can comprise a rotatablesleeve 120, a grip portion 122, and a retaining ring 124. The rotatablesleeve 120 can be disposed on a housing 150 positioned about anarticulating joint coupled to the transfer member 28. In someembodiments, the housing 150 can comprise a two-piece housing includinga first portion 154 and a second portion 156. In other embodiments, thehousing 150 can include more or fewer than two pieces. In still otherembodiments, the rotatable sleeve 120 can be configured to be disposedon an upper end of the transfer member 128 with no housing present.

In some embodiments, the rotatable sleeve 120 can comprise a firstportion 121 and a second portion 123. Each of the first and secondportions 121, 123 can include a generally cylindrical portion configuredto underlie the grip portion 122 and a flanged lip configured to retainthe grip portion 122. In the illustrated embodiment, this two-piecerotatable sleeve 120 can be easily installed on the housing 150 duringmanufacture of the PCMM 10. In other embodiments, the rotatable sleeve120 can be formed as a single unitary component. The rotatable sleeve120 can have generally cylindrical shape having flanged lips at firstand second end thereof to retain a gripping portion 122. Desirably, therotatable sleeve 120 can be constructed of material having a relativelylow coefficient of friction such that it can freely rotate with respectto the housing 150 and the retaining ring 124. In some embodiments therotatable sleeve 120 can be constructed of the same material as therotatable sleeve 110 of the lower rotatable grip 102. In otherembodiments, the rotatable sleeve 120 can be constructed of one of avariety of different materials having the desired properties.

With continued reference to FIGS. 3 and 4, and the grip portion 122 ofthe upper rotatable grip 104 can have a generally cylindrical shape andbe sized to snugly fit over the rotatable sleeve 120. The grip portion122 can comprise a relatively soft material such as natural or syntheticrubber, or a silicone rubber for operator gripability and comfort. Inthe illustrated embodiment, the rotatable sleeve 120 and a grip portion122 are separately formed such that the rotatable sleeve 120 can allowfor free rotation of the rotatable grip and the grip portion 122 canprovide enhanced operator gripability and comfort. In some embodiments,the grip portion 122 can be relatively elastic can be stretch fit overthe rotatable sleeve 120. In some embodiments, the grip portion 122 canbe adhered to the rotatable sleeve 120 using an adhesive or epoxy.However, in other embodiments, the rotatable sleeve 120 and the gripportion 122 can be integrally formed from a material having satisfactorymaterial properties with respect to friction and operator comfort.

With continued reference to FIGS. 3 and 4, to further enhance thegripability of the grip portion 122, in some embodiments, the gripportion 122 can include gripping features such as, for example, one ormore dimples or indentations 123, one or more protrusions or ridges, orsurface texturing. Advantageously, this enhanced gripability can reducethe likelihood an operator's hand will slip from the rotatable grip 104when the operator is positioning the PCMM 10.

With continued reference to FIGS. 3 and 4, the retaining ring 124 canmaintain an axial position of the upper rotatable grip with respect tothe transfer member 28 and the housing 150. In some embodiments, theretaining ring 124 can be constructed of a metallic material and can besized to be press fit onto the housing 150 and to limit axial movementof the ring 124 on the housing 150 once positioned. In otherembodiments, the retaining ring 124 can comprise a nonmetallic materialsuch as a plastic, composite material, or other material. Desirably, theretaining ring 124 can be constructed of a material having materialproperties and a surface finish that allow the rotatable sleeve 120 tofreely rotate. In some embodiments, the housing 150 can comprise arecess 126 formed therein against which an end of the rotatable sleeve120 can abut. Accordingly, in some embodiments the upper rotatable grip104 comprises a single retaining ring 124 to restrict axial movement ofthe rotatable grip 104. In other embodiments, the upper rotatable grip104 can comprise two retaining rings, positioned at opposite ends of therotatable sleeve 120 to restrict axial movement thereof. In otherembodiments, a recess formed in the housing 150 can restrict axialmovement of the rotatable sleeve 120 at each end of the rotatable sleeve120.

With respect to FIGS. 1-4, joint housings 150, 152 are illustrated whichcan at least partially encase portions of several of the articulationmembers 42, 44, 46, 48. As discussed above with respect to FIGS. 3 and4, in some embodiments a joint housing 150 can comprise a two-piecehousing including a first housing portion 154 in the second housingportion 156, and can include a rotatable joint 104 disposed thereon. Inother embodiments, the joint housings 150, 152 can be unitarily formed,and in other embodiments, the joint housings 150, 152 can comprise morethan two portions such as, for example, three portions or four portions.

Advantageously, the two-piece joint housings 150, 152 illustrated in theembodiments of FIGS. 1-4, can be relatively inexpensively manufacturedand assembled. Also, desirably, the joint housings 150, 152 can providea uniform aesthetic appearance to the PCMM 10. The joint housings 150,152 can likewise protect the articulation members 42, 44, 46, 48 fromimpacts and exposure to dust or debris.

With reference to FIGS. 1-2 and 5A-5B, a probe caddie 200 isillustrated. The probe caddie 200 can allow an operator to quickly andeasily switch probes 202, 204, 206 on the PCMM 10. The probe caddie 200can include a body 210 having recesses 212, 214, 216 formed therein. Thebody 210 can have an edge 220 having a curved profile configured tocouple to a transfer member 24 of the PCMM 10 such as with a fastener,welding, an adhesive, or snap-fit. Desirably, the probe caddie 200 canbe coupled to the PCMM 10 at a location near the base 20 such that anoperator can have easy access to the probes stored therein and controlson the base 20 and such that the probe caddie 200 does not affect themeasuring operation of the PCMM 10. In other embodiments, the probecaddie 200 can be shaped and configured to couple at a differentlocation with of the PCMM 10, such as, for example, the base 20.

With reference to FIGS. 5A and 5B, the probe caddie 200 can include aplurality of recesses 212, 214, 216 formed therein and configured toreceive a corresponding plurality of probes 202, 204, 206. In theillustrated embodiment, the probe caddie 200 comprises three recesses212, 214, 216 to receive the corresponding three probes 202, 204, 206.In other embodiments, however, more or fewer than three recesses can beincluded in the probe caddie 200 to allow the probe caddie to retain adesired number of probes. Each of the recesses 212, 214, 216 can includeone or more retention members 222 to selectively retain a probe receivedtherein. In the illustrated embodiment, the retention members 222comprise tabs formed in the body 210 of the probe caddie 200. In theillustrated embodiment, the tabs can be biased into a retention positionsuch that they tend to retain a probe in recess. The tabs can besufficiently flexible to allow an operator to withdraw a probe from orreplace a probe into the recess as desired. In other embodiments, otherretention members or latches can be used to selectively retain a probe.In the illustrated embodiment, each of the recesses 212, 214, 216 has asimilar size and configuration. In other embodiments, recesses havingdifferent sizes and/or configurations can be provided to retain probeshaving different sizes or configurations.

With reference to FIGS. 5A and 5B, in various embodiments, the probecaddie 200 can be constructed of various materials. For example, in someembodiments the probe caddie 200 can be constructed of a thermoplasticmaterial. In other embodiments, the probe caddie 200 can be constructedof a metallic material.

With continued reference to FIGS. 5A and 5B, probes 202, 204, 206 can beprovided for use with the PCMM 10 that, in conjunction with the probecaddie 200 allow for ease and speed in switching probes on the PCMM 10.For example, the probes 202, 204, 206 can be configured to allow rapidlyrepeatable kinematic mounting. In some embodiments, the probes caninclude push pin connectors 230 to electrically couple each probe 202,204, 206 to the PCMM 10 when in use. The probes 202, 204, 206 can alsoinclude alignment features, such as grooves 232 formed therein to allowrepeatable mounting at a desired alignment with the PCMM 10.

Although this application has been disclosed in the context of certainpreferred embodiments and examples, it will be understood by thoseskilled in the art that the present inventions extend beyond thespecifically disclosed embodiments to other alternative embodimentsand/or uses of the inventions and obvious modifications and equivalentsthereof. In addition, while the number of variations of the inventionshave been shown and described in detail, other modifications, which arewithin the scope of this inventions, will be readily apparent to thoseof skill in the art based upon this disclosure. It is also contemplatedthat various combinations or subcombinations of the specific featuresand aspects of the embodiments may be made and still fall within thescope of the inventions. Accordingly, it should be understood thatvarious features and aspects of the disclosed embodiments can becombined with, or substituted for, one another in order to performvarying modes of the disclosed invention. Thus, it is intended that thescope of the present inventions herein disclosed should not be limitedby the particular disclosed embodiments described above, but should bedetermined only by a fair reading of the claims.

1. A coordinate measuring machine comprising: a first transfer member; a second transfer member; an articulating joint assembly rotatably coupling the first transfer member to the second transfer member; a probe connected to the transfer members and the joint assembly; a rotatable grip assembly disposed on an outer surface of one of the first transfer member and the second transfer member; a housing disposed about at least a portion of the articulating joint assembly; and a second rotatable grip assembly disposed on the outer surface of the housing.
 2. The coordinate measuring machine of claim 1, wherein at least one rotatable grip assembly comprises: a rotatable sleeve disposed about one of the first transfer member and the second transfer member; and a grip portion disposed about the rotatable sleeve.
 3. The coordinate measuring machine of claim 2, wherein the grip portion comprises a plurality of dimples formed therein.
 4. The coordinate measuring machine of claim 1, wherein at least one rotatable grip assembly comprises a first retention ring positioned about the transfer member on which the at least one rotatable grip assembly is disposed.
 5. The coordinate measuring machine of claim 4, wherein the at least one rotatable grip assembly further comprises a second retention ring positioned about the transfer member on which the rotatable grip assembly is disposed.
 6. The coordinate measuring machine of claim 1, wherein the probe is coupled to an end of one of the first transfer member and the second transfer member; and further comprising a probe caddie disposed on the coordinate measuring machine and adapted to receive at least one probe.
 7. A coordinate measuring machine comprising: a base; a first transfer member coupled to the base; a second transfer member rotatably coupled to the first transfer member by a first articulation joint assembly; a third transfer member rotatably coupled to the second transfer member by a second articulation joint assembly; a probe connected to the transfer members; a probe caddie coupled to the first transfer member, the probe caddie configured to receive one or more probes; and a rotatable grip assembly disposed on the third transfer member.
 8. A coordinate measuring machine comprising: a base; a first transfer member coupled to the base; a second transfer member rotatably coupled to the first transfer member by a first articulation joint assembly; a third transfer member rotatably coupled to the second transfer member by a second articulation joint assembly; a probe connected to the transfer members; a first rotatable grip assembly disposed on the third transfer member; and a housing disposed about at least a portion of the second articulation joint assembly and a second rotatable grip assembly disposed on the housing.
 9. The coordinate measuring machine of claim 8, wherein the housing further comprises a recess configured to receive the second rotatable grip assembly.
 10. The coordinate measuring machine of claim 8, wherein the second rotatable grip assembly comprises a rotatable sleeve and a grip portion.
 11. The coordinate measuring machine of claim 10, wherein the rotatable sleeve comprises a first portion and a second portion.
 12. The coordinate measuring machine of claim 8, further comprising a probe caddie coupled to the first transfer member, the probe caddie configured to receive one or more probes.
 13. The coordinate measuring machine of claim 8, wherein at least one rotatable grip assembly comprises a rotatable sleeve and a grip portion.
 14. The coordinate measuring machine of claim 13, wherein the at least one rotatable grip assembly further comprises a retaining ring configured to prevent axial movement of the rotatable grip assembly relative to the third transfer member.
 15. A coordinate measuring machine comprising: a base; a first transfer member coupled to the base; a second transfer member rotatably coupled to the first transfer member by a first articulation member; a third transfer member rotatably coupled to the second transfer member by a second articulation member; a first housing disposed about at least a portion of the first articulation member; a second housing disposed about at least a portion of the second articulation member; a first rotatable grip assembly disposed on the third transfer member and rotatable about a longitudinal axis defined by the third transfer member; a second rotatable grip assembly disposed on the second housing and rotatable about the longitudinal axis; and a probe connected to the transfer members.
 16. A coordinate measuring machine comprising: a first transfer member; a second transfer member; an articulating joint assembly rotatably coupling the first transfer member to the second transfer member; a first probe connected to the transfer members; and a probe caddie disposed on at least one of the transfer members of the coordinate measuring machine and adapted to receive at least one probe.
 17. The coordinate measuring machine of claim 16, wherein the first probe is coupled to an end of one of the first transfer member and the second transfer member.
 18. The coordinate measuring machine of claim 16, wherein the probe caddie is adapted to receive at least three probes.
 19. The coordinate measuring machine of claim 16, wherein the probe caddie comprises at least one retention member biased to retain at least one probe. 